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Polyoxyl Lauryl Ether

Polyethylene glycol monolauryl ether [9002-92-0].
» Polyoxyl Lauryl Ether is a mixture of the mono-lauryl ethers of mixed polyethylene glycols, the average polymer length being equivalent to not less than 3 and not more than 23 oxyethylene units (nominal value). It contains various amounts of free lauryl alcohol, and it may contain some free polyethylene glycols.
Packaging and storage— Preserve in tight containers, and store in a cool, dry place.
Labeling— Label it to indicate the average nominal number of oxyethylene units.
USP Reference standards 11 USP Polyoxyl Lauryl Ether RS.
Appearance of solution— Dissolve 5.0 g of Polyoxyl Lauryl Ether in 50.0 mL of alcohol, and proceed as directed for Appearance of solution under Polyoxyl Stearyl Ether.
Identification—
A: Infrared Absorption 197F—Use a thin film of melted test specimen if the material is a solid.
B: Dissolve or disperse 0.1 g in 5 mL of alcohol, add 10 mL of diluted hydrochloric acid, 5 mL of barium chloride TS, and 10 mL of phosphomolybdic acid solution (1 in 10): a precipitate is formed.
Acid value 401: not more than 1.0, determined on 5.0 g.
Hydroxyl value 401: within the ranges specified in the accompanying table.
Oxyethylene Units per
Molecule (Nominal Value)
Hydroxyl Value
3 165–185
4 145–165
5 130–140
9 90–100
10 85–95
12 73–83
15 64–74
20–23 40–60
Iodine value 401: not more than 2.0.
Saponification value 401: not more than 3.0, determined on 10.0 g.
Alkalinity— Dissolve 2.0 g of Polyoxyl Lauryl Ether in a hot mixture of 10 mL of alcohol and 10 mL of water. Add 0.05 mL of bromothymol blue TS, and titrate with 0.1 N hydrochloric acid to a yellow endpoint: not more than 0.5 mL of 0.1 N hydrochloric acid is required.
Water, Method I 921: not more than 3.0%.
Total ash 561: not more than 0.2%, determined on 2.0 g.
Limit of free ethylene oxide and dioxane— Proceed as directed for Limit of free ethylene oxide and dioxane under Polyoxyl Stearyl Ether. Not more than 1 µg per g of free ethylene oxide is found; and not more than 10 µg per g of dioxane is found.
Auxiliary Information— Staff Liaison : Hong Wang, Ph.D. , Senior Scientific Associate
Expert Committee : (EM205) Excipient Monographs 2
USP29–NF24 Page 3403
Pharmacopeial Forum : Volume No. 29(4) Page 1117
Phone Number : 1-301-816-8351